Reaktion #580581

Reaktionsgleichung

(S)-tert-butyl 2-(((9H-fluoren-9-yl)methoxy)carbonylamino)-3-(6-bromo-pyridin-3-yl)propanoate

2-ethylphenylboronic acid

sodium carbonate

→

expected compound

Ausbeute 59.0%

(S)-tert-Butyl 2-(((9H-fluoren-9-yl)methoxy)carbonylamino)-3-(6-(2-ethyl-4-methoxyphenyl)pyridine-3-yl)propanoate

Ausbeute 59.0%

Lösungsmittel

isopropanol toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe reaction mixture was purged twice with argon
2. 2
   Sonstigeevacuated
3. 3
   Sonstigethe mixture was again purged with argon
4. 4
   Sonstigeevacuated
5. 5
   Temperaturthe reaction mixture was cooled to room temperature
6. 6
   Einengenpartially concentrated
7. 7
   Sonstigeto remove isopropanol
8. 8
   SonstigeThe residue was partitioned between ethyl acetate and water
9. 9
   Extraktionthe aqueous phase was extracted once more with ethyl acetate
10. 10
    Trocknendried over magnesium sulfate
11. 11
    Filtrationfiltered
12. 12
    Einengenconcentrated
13. 13
    Sonstigeto give a brown oil
14. 14
    SonstigePurification by chromatography on silica gel

Vorschrift

To a stirred slurry of 613 mg (1.17 mmol) of (S)-tert-butyl 2-(((9H-fluoren-9-yl)methoxy)carbonylamino)-3-(6-bromo-pyridin-3-yl)propanoate and 422 mg (2.34 mmol, 2 eq.) of 2-ethylphenylboronic acid in 20 mL of 1:1 isopropanol/toluene was added 10.0 mL of 2 M aqueous sodium carbonate solution. The reaction mixture was purged twice with argon and evacuated and then 43.2 mg (0.059 mmol, 0.05 equivalents) of bis(tricyclohexylphosphine)palladium (II) chloride was added and the mixture was again purged with argon and evacuated. The rapidly stirred mixture was heated at 80° C. under argon. After 9 h, the reaction mixture was cooled to room temperature and partially concentrated to remove isopropanol. The residue was partitioned between ethyl acetate and water and the aqueous phase was extracted once more with ethyl acetate. The organic extracts were combined, dried over magnesium sulfate, filtered and concentrated to give a brown oil. Purification by chromatography on silica gel using ethyl acetate/dichloromethane (3:17) as eluant (5×15 cm column), gave the expected compound as a colorless oil, 401 mg, 59% yield.

Quelle